No anatomical joint exists between each scapula and the rib cage; instead the muscular connection or physiological joint between the two permits great mobility of the shoulder girdle compared to the compact pelvic girdle; because the upper limb is not usually involved in weight bearing, its stability has been sacrificed in exchange for greater mobility.

The gliding movements at the scapulocostal joint are elevation, depression, retraction, protraction and superior and inferior rotation of the scapula.

From its neutral position, the shoulder girdle can be rotated about an imaginary vertical axis at the medial end of the clavicle (the sternoclavicular joint).

[4]: 40 Shoulders are a common place for tissue injuries, especially if the person plays overhead sports such as tennis, volleyball, baseball, swimming, etc.

[7] In humans, winged scapula is a condition in which the shoulder blade protrudes from a person's back in an abnormal position.

Except for the sternum, these elements (along with the pelvic girdle) were, however, present in early bony fishes before there were even limbs, arising from their ancestral external armor plates.

In digitless choanates, the cleithrum, clavicle, and interclavicle are dermal and linked to the caudal part of the head while the humerus articulates with a small scapulocoracoid bone.

As the first digits appeared, the pectoral structure lost its direct connection to the head skeleton while the scapulocoracoid grew more prominent and started to face laterally.

In true tetrapods, the dermal part of the girdle was gradually reduced and the scapulocoracoid split into a dorsal scapula and a ventral coracoid.

In dinosaurs, the main bones of the pectoral girdle were the scapula (shoulder blade) and the coracoid, both of which directly articulated with the clavicle.

Their clavicles possess a cranially oriented twist on the acromial end, conducive to better force transfer through it - a very important function in arboreal locomotion.

Through the process of evolution, humans have lost the atlantoclavicularis muscle, originating on the atlas of the vertebral column, and inserting onto the acromial clavicle.

[9] A specimen of the placoderm Kolymaspis demonstrates that the shoulder girdle evolved from gill arches present in ancient vertebrates.